• Rome has had a busy few days. Before advising the faithful on the uses and abuses of social media, the pope warned American bishops of "powerful new cultural currents which are not only directly opposed to core moral teachings of the Judeo-Christian tradition, but increasingly hostile to Christianity as such". He urged them to help the entire Catholic community in the US become aware of the dangers posed by "radical secularism" and foster an "engaged, articulate" laity.

• The pontiff also took part in one of the most charming rituals of the Catholic calendar: the presentation of the lambs blessed on the feast of St Agnes. These are the lucky ovids from whose wool the pope's pallium will be made. The blessing is held each year in the church of Sant'Agnese fuori le mura. Rome Reports has a video of the presentation, which took place at the Apostolic Palace.

• A thousand-odd miles to the north-west, the storm over the closure of the Irish embassy to the Holy See gathers force. The Ireland Stand Up campaign aims to reverse the government decision, blamed on straitened finances, and ask Pope Benedict to visit the Emerald Isle. Given the budgetary pressure he is under, the prime minister, Enda Kenny, is unlikely to be swayed – even by the 96,000 postcards campaign supporters are reported to have sent him.

• Another video from Rome Reports, if you can bear the schmaltzy music: the intriguing story of Etsuro Sotoo, a former professor of art at Kyoto University, who converted to Catholicism after working on sculpture for Barcelona's Sagrada Familia cathedral. Sotoo says: "I tried to look in the way that Gaudi did … I tried to do what he would have done. This was the magnificent and miraculous moment."

• Violence continues to beset Nigeria, particularly in the north of the country and the "middle belt", where the Christian south shades into the predominantly Muslim north. Responsibility for some of the latest instances of sectarian killing has been claimed by members of a movement known as Boko Haram, who identify themselves as Salafis – imitators of the earliest followers of Muhammad – but whose teaching seems at odds with centuries of Islamic tradition. Attacks in the city of Kano on 20 January killed nearly 200, while a report released this week by Human Rights Watch suggested that Boko Haram had been responsible for 935 deaths since 2009.

• Reuters provides a fascinating insight into the world of Senegal's Muslim "brotherhoods", as benign a presence in that country as Boko Haram is menacing in Nigeria. The Mourides, members of an idiosyncratic order of Sufis, are being courted by president Abdoulaye Wade in the runup to next month's elections.

• And our very own Brian Whitaker brings news of change in the Saudi religious police, the Commission for the Promotion of Virtue and Prevention of Vice, following the appointment of Sheikh Abdullatif al-Sheikh as chief last month. A relative moderate in the context of Saudi Arabia, he appears to be reforming the much-feared institution. In a measure that may go some way to preventing abuse of what some would regard as an inherently abusive system, the commission will not respond to reports "unless the person making the complaint identifies himself or herself" and "the information is verified".